This invention relates generally to irrigation sprinklers of the type designed to provide one or more outwardly directed irrigation streams which are rotatably swept through a prescribed arcuate path. More particularly, this invention relates to a compact and relatively simple sprinkler nozzle for providing multiple discrete rotating irrigation water streams, wherein the nozzle directly incorporates efficient drive means for indexing the discrete streams in a stepwise manner through a prescribed arcuate spray path.
Irrigation sprinklers are well known of the general type designed to provide one or more outwardly projected streams of irrigation water. Such irrigation sprinklers traditionally include a sprinkler body having one or more spray nozzles mounted thereon, wherein the sprinkler body is rotatable for sweeping the discharged water stream or streams through a prescribed arcuate spray path, such as a part-circle or full-circle path, to irrigate surrounding vegetation. In this regard, the sprinkler further includes a rotary drive mechanism, for example, an impact or reaction drive mechanism which is water-driven to rotate the sprinkler body in a manner delivering the irrigation water over the prescribed spray path. Other types of rotary drive mechanisms include water-driven turbines and drive balls for rotating at least the portion of the sprinkler body carrying the spray nozzle resulting in water distribution over the desired terrain area.
In some specialized irrigation applications, it is desireable to deliver irrigation water to surrounding terrain at a relatively slow precipitation rate primarily to avoid excess water run-off and waste. In addition, it is sometimes desirable to provide such low precipitation rates by use of a relatively small number of irrigation sprinkler devices to correspondingly minimize system cost and complexity including, for example, the required number of sprinkler heads and related piping and controls. To this end, rotating stream sprinklers have been developed to provide multiple dicrete water streams which are projected outwardly with substantial range but at a relatively low flow rate. Such sprinklers have included internal drive mechanisms for rotating the water streams typically in a succession of small steps through a prescribed part-circle or full-circle spray path. However, in the multiple stream rotating sprinklers of this type, the drive mechanisms have been limited to relatively complex and normally bulky turbine drive, ball drive, and/or gear drive structures, thereby rendering such sprinklers relatively costly and unduly complicated in construction. Efforts to provide simplified drive arrangements in sprinklers of this type have generally been unsuccessful due, for example, to the difficulties in obtaining predictable and/or efficient stepwise driving as a result of the complex combination of reaction and rotational forces encountered in such sprinklers.
The improved rotating stream nozzle of the present invention overcomes these problems and disadvantages by providing a compact and simple sprinkler nozzle designed to provide multiple discrete streams rotated through a prescribed arcuate spray path, wherein the sprinkler nozzle directly incorporates a simple yet efficient drive means for stepwise displacement of the discrete water streams.